Display apparatus



March 9 1926. 1,576,201

' L. R. MCDONALD DI SPLAY APPARATUS Filed July '7, 1925 2 Sheets-Sheet 1 -Marcb. 9 1926.

. 1,576,201 5.... R. M DONALD DISPLAY APPARATUS Filed July 7, 1925 2 Sheets-Sheet 2 ATTORNEY.

Patented 9, 1926.

.UN'ITED STATES PAT ur OFFICE.

LESLIE R. MCDONALD, or MONTREAL. QUEBEC, CANADA.

DISPLAY APPARATUS.

Application filed July 7, 1925. .Serial No. 41,908.

; To all 10. mm it may concern.

rearmost placard so as to allow it to fall forward into view position, and also to means for holding down the free end of the next placard during. that operation to prevent its being displaced by adhesion to its predecessor.

My invention, which is an improvement upon the apparatus described in my Letters Patent of the United States, No. 1,539,682, dated May 26th, 1925, will be readily understood by reference to that patent and the drawings, accompanying this specification and the description herein contained.

In the drawings, Fig. 1 is a rear elevation of an apparatus showing an embodiment of my invention, the back of the case being removed and its top broken away; Fig. 2 is a side elevation, looking to the left on Fig. 1, the side of the case being removed, the lower end of the rack bar and arm broken away and the suction pump being shown in vertical section; Fig. 3 is a detail of the upper end of the suction pump and the lifting suction head, which shortened toward its right hand end by the omission of medial portions; Fig. 4 is a similar view of the down holding suction head; Fig. 5 is a detail, taken as looking to the right on the line 5-5 of Fig. 3; and Fig. '6 is a similar detail taken as looking to the right ontlie line 6-6 of Fig. 4. l

In all the figures similar reference numerals designate similar parts.

Thecase 1 is provided, as usual, with an open or glazed front 2, behind which the placards are successively exhibited, and is also provided with brackets 3, 3 supporting a frame 4 by which the operating mechanism may be carried. This operating mechanism includes a motor 5, the shaftfi of which is provided with a worm 7, meshing with a worm gear 8 fixed on a shaft 9, upon the inner end of which is journalled a pawl arm 10, the detent ll of which engages with the teeth 12, 12 on thedisk 13, and is nor-' mally pressed up against the same by the rotation of the shaft 9. The shaft 9 also carries an eccentric 14 upon which is mounted the feeding pawl 15 which is reciprocated by the rotation of the eccentric, so that its detent 16 will engage with the teeth 12, 12 and turn the disk 13 one step for each revolution of the shaft 9.

' The further details of the construction and interrelation of this portion of the driving mechanism for the placard carrier assembly are similarto those shown in my Letters Patent No. 1,539,682, of May 26, 1925, and No. 1,477,887, of December 18th, 1923, and it is therefore unnecessary to describe them further herein. The operation of the mechanism results in turning the placard carrier forward step by step.

Mounted on and turned by the shaft 9 is a segmental gear wheel 20 meshing with a rack. bar 21, sliding in a suitable guide 22 attached to the case 1, and being connected, as by arm 23 and brace 24, with the casing 25 of a pneumatic pump, the hollow piston 26 of which is carried by a base 27 attached to the bottom of the case 1. i

A tube 28 extends from thetop of the casing 25 to and carries a cross head 30, which is provided with a channel 31, communicating with the bore of the tube 28 and also with several flaring openings 32 in the forward side of the cross head 30.

- The base of the piston shank 26 communica tes, through a tube 35 with a cross head.

36 having a channel 3'? communicatingwith the bore of the tube 35 and also with several flaring openings. 38 the cross head 36..

The normal, initial positions of the parts are those shown in the drawings, with the cross head 30 behind and against the rearniost placard and with the cross head 36 bein the forward side of hind andagainst the end of the next placard.

In operation, for each step that the placard carrier is turned. forward the segmental gear '20 will be given one complete revolution. Thisrevolution lifts therack bar 21, which carries up with it the pump casing 25, producing a partial vacuum in the pumpwith consequent suction inthrough th openings 32, 32 in the cross head 30,

causing the rearmost placard 40 to adhere to openings38, 38 in the cross head 36 causing the free end of the next placard 4:1 to adhere to the cross head sothat the placard 4.1 will be held down by the cross head during the upward mmement of the placard L0. This overcomes any tendency of these two placards to hang together, under the influence of static electricity or otherwise.

hen the segmental gear 20 has com pleted its arc of operative engagement with the rack bar 21, the bar will be released and willslide down to its initial position, carrying the pump casing with it, eliminating the partial vacuum in the, pump, and releasing the placard ends from its influence, so that the placard tO may fall forward over the carrier and the other free placard ends may be raised a step so that the end of placard ll will register in theformer position of placard 40, and another placard will be moved into the former position of placard 41; andthe cycle of operations above described will then recur.

The influence 'of the partial'vacuum With in the pump may be modified, for instance, by making the cross heads of wood, which will afford a certain amount of leakage, or by employing material more or less impervious to airsuch as metal or rubber.

Means, such as a regulating valve 45, may also be employed for modifylng the amount of suction exerted by the pump, as experience may require. 7

It will be understood that'in illustrating the use of a segmental gear and a rack bar for reciprocating the pump I have used them as typesof mechanism suitable for producingvsuch movement, and that mechanical equivalents for these elements might be substituted without departing from the spirit of my invention or the scope of my claims. Th same may also be said of the other elements which I have shown in the particular embodiment of my invention which I have shown and described.

Itwill be seen that the engagement of the cross heads with the placards is of sufficient extentto avoid slipping, and is positive, so as practically to eliminate damage to the placards by wear,,as there is no material friction produced by a sliding movement between the placards and the heads.

By. my improvements I securea positive, simple and efficient feeding mechanism, by the use of which placardsmay be lifted and thrown forward one; by one while the other placards in the roll will be held against disarrangement by adhesion to'the last one. This is peculiarly desirable with long placards which will not fall forward and unroll to their full lengths simply under their own weight. But the principle is also applicable to shorter placards when precision ard carrier, a series of flexible phicards each attached by one end thereto and partially rolled thereupon with their free ends depending therefron'i, and suctional means for engaging and lifting the free end of a placard. a

2. In a display apparatus, the combination of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially rolled thereupon with their free ends depending therefrom, and suctional means for engaging and lifting the free end of each placard successively.

3; In a display apparatus, the combination of rotating means and a. rotatable placard carrier, a series of flexible placards each attached by one end thereto and-par tially rolled thereupon with their free ends depending therefrom, and suctional means for engaging and holding down the free end of a placard.

4. In a display apparatus, the combination of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto, and partially rolled thereupon with their free ends depending therefrom, and suctional means for engaging and holding downthe free end of each placard successively.

5. In a display apparatus, the combination of rotating means and a rotatable placard carrier, aseries. of flexible placards each attached by one endthereto and partially rolled thereupon with their free ends depending therefrom, suctional means for engaging and lifting the free end of a placard and suctional means for engaging and holding down the free end of anotherplacard. I t

6 In a display apparatus, the combination of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially roll-ed thereupon with their free ends depending therefrom, common means for producing partial vacuum, placard raisi'ng means operated by saidcommon means, and placard down holding means also operated by said common means.

7. In a display apparatus, the combination ofstep by step rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially rolled thereupon with their free ends depending therefrom, means for engaging and lifting the free end of a placard and means for engaging and holding down the free end of another placard between the steps of carrier rotation.

8. In a display apparatus, the combination of step by step rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially rolled thereupon with their free ends depending therefrom and means for engaging and holding down the free end of a placard between the steps of carrier rotation.

S). In a display apparatus, the combination of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially rolled thereupon with their free ends depending therefrom, and suctional means embodying a head having a plurality of suction openings therein for engaging and lifting the free end of a placard.

10. In a display apparatus, the eombina tion of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto andv partially rolled thereupon with their free ends depending therefrom, and suctional means, lncluding a pneumatic suction pump, for en gaging and lifting the free end of a placard.

.tially rolled thereupon with their free ends depending therefrom, suc-tional means, embodying a head having a plurality of openings the-rein, for engaging and lifting the free end of a placard, and sectional means embodying ahead having a plurality of openings therein, for engaging and holding down the free end of another placard.

12. In a display apparatus, the combination of rotating means and a rotatable placard carrier, a series of flexible placards each attached by one end thereto and partially rolled thereupon with their free ends depending therefrom, means for intermittently creating a partial vacuum, means rendered ei'licient thereby for lifting the free end of a placard, and other means rendered efficient by said partial vacuum for holging down the free end of another placar LESLIE RQMCDONALD. 

